Production of aminoalkyl sulphonic acids



ethanol amines, as

Patented Apr. 30, 1935 PRODUCTION OF AlVIINOALKYL SULPHONIC ACIDS Heinrich Ulrich and Paul 'Koerding, Ludwigs hafenon-the-Rhine,

and Ottmar Wahl, Leverkusen, Germany, assignors to I. G. Farbenindustrie Aktiengesellschaft,

Main, Germany Frankfort-'on-the- No Drawing. Application October'll, 1932, Se-

rial No. 637,282. In Germany 15 Claims.

The present invention relates to the productionof aminoalkyl sulphonic acids.

We have found that aminoalkyl sulphonic acids, of the basic type of-taurine (HaN-CzH4-SO3H) can be obtained in a simple manner by causing mineral acid esters of hydroxyalkylamines, including salts of said esters, to react with neutral alkali, i. e. ammonium, alkali metal or alkaline earth metal, salts of sulphurous acid in the presence of some water. The quantity of water employed may be very small and even traces thereof are apparently. sufficient to initiate the reaction. For the sake of easy working the quantity of water employed is, however, generally chosen at least equal to that of the mineral acid ester employed and, preferably, equal to that .of both reaction components. also further increased though we prefer such quantities of water from which the reaction product crystallizes so that 'a subsequent removal of water, for example by distillation, can be avoided in most cases. 9

For this process water-soluble salts of the latter, from strong, non-oxidizing mineral acids are preferred, such as those of sulphuric and phosphoric acids and halogen hydraclds, Whereas those from weak mineral acids, such as boric acid, and from nitric acid are less suitable. The acid sulphuric acid esters of hydroxyalkylamines,which are obtainable for example according to the present inventors and anothers application for U. S. patent No. 534,689 filed May 2, 1931, or salts of said acid esters, are especially suitable;. specific examples of such sulphuric esters are those of the for example mono-, dior 'tri-ethanol amines, N-hydroxyethyl aniline, N- ethyl N-hydroxy-ethyl aniline, N-hydroxyethyl diphenylamine, N-hydroxy-ethyl-N-benylamine,

N-hydroxyethyl piperidine, N-methyl-N-hydroxy-ethyl-N-oleyl amine, N -hydroxyi sopropyl- N-methyl alpha naphthylamine, N beta-hydroxy-n-butyl-N-ethyl aniline om-omonponr-ona) N-beta-hydroxy-n buty1 N-ethyl-alphaandbetanaphthyl-amines, N-beta-hydroxy-n butyl di phenyl amine, N-gamma-hydroxy-n-butyhN n-butyl amine, N hydroxypropyl .cyclohexyl amine, N-hydroxyethyl-N benzylcyclohexyl- It may be the neutral or acid esters or may be chosen from ammonium,

R and R1 being hydrogen or any October 20, 1931 (Cl. 260-129) v amine, N-butyl-N-hydroxy-isopropl aniline and.

similar N- aryl-N-hydroxyaliwlv amines corresponding to the general formula RN -R2 in which R denotes. hydrogen or any alkyl, cycloalkyl, aryl or aralkyl radicle, R1 denotes an aryl or aralkyl radicle, such as phenyl, tolyl, xyiyl, naphthyl or benzyl radicles, and R2 denotes a hdroxyalkyl radicle. Corresponding halogen hydracid esters, as for examplebutyl chlorethylamine, or the corresponding bromides or iodides, and phosphoric esters and water-soluble salts thereof, especially the alkali metal salts, may also be employed. In most cases the reaction proceeds more easily with esters of tertiary amines than with primary and secondary amines. As pointed out above, water-soluble salts of the-mineral acid esters may be employed in the place of the acid mineral acid esters. Otherwise, the reaction mixture may be rendered neutral with the aid of alkali as the reaction is preferably carried out'in a neutral or slightly alkaline medium.

The reaotion with-the salts of sulphurous acid is generally carried out in aqueous solution while warming in a closed vessel, generally to from about C. to about 180 C. Temperatures above C. are, however, frequently disadvantageous because decomposition of the initial materials may then take place. If desired watersoluble; neutral and inert organic diluents, such as ethyl alcohol, ethylene glycol, acetone and the like, may be added. The neutral alkali sulphites sodium, potassium, lithium, calcium, barium, strontium and magnesium sulphites; the easily water-soluble alkali metal sulphites, as for example sodium and potassium sulphites and ammonium sulphite, are especially suitable for the process. Advantageously the sulphites are employed inpslight excess to the quantities theoretically required; the following equation indicates by way of example the course of the reaction:

hydrocarbon radicle, such as alkyl, cycloalkyl, aryl or aralkyl radicles or R and R1 may form a heterocycllc nucleus with the nitrogen atom, alkylene group.

. The process according to the present invention offers special advantages in so far as it allows while R2 is an for hours in a closed vessel.

of preparing from readily accessible mineral acid esters of hydroxy-alkylamines the corresponding sulphonic acids free from undesirable by-proddyestufis, pharmaceutical preparations and the like may be obtained.

The following examples will further illustrate the nature of this invention but the invention is not restricted to these examples. The parts are by weight.

A solution of 140 parts of mono-hydroxyethyl amine sulphuric ester in 300 parts of water is purified after cooling the reaction mixture. The

reaction proceedsinaccordance with the equation:

Example 2 an autoclave at 155 C. for The resulting solution is mixture is heated in about 5 hours.

C. N- butyl-N-phenyl which separates out in the form of leaflets, is filtered off by lea-CURL In this manner a yield oi about 80 per Cent of the theoretical yield is Example 4 220 parts of, the sodium salt of N-hydroxyethyl- -benzyl-aniline sulphuric ester are dissolved in 400 parts of water and heated together with 150 parts of 85 per cent sodium sulphite to 165 C.

The resulting reaction mass is filtered while hot after the addiis precipitated in the filtered phuric ester of tion of 200 parts of water. When theflltrate is cooled, the sodium salt 01' N be'nzyl-N-phenyl taurine 6H6 CHl\ NCHzCHr-SO1NB) CIHI separates out in-the form of white leaflets. The product may be purified by recrystallization from hot water, if necessary after an extraction with ethyl ether. The free acid may be obtained from cooling, 300 parts of a 25 per cent aqueous sulphuric acid solution are added, whereby N-ethyl- N -alphanaphthyl taurine form of fine leaflets. The product can be purified by recrystallization from hot water.

Ewample 6 What we claim is:. 1. The process for the production of aminoalkyl sulphonic acids which comprises reacting a mineral acid ester of an amine containing at least one hydroxyl group attached to a low molecular alkyl radicle, with a neutral alkali metal salt of sulphurous acid in the presence of water.

' alkyl radicle, with a neutral nose-pea radicle, and a halogen hydracid with a neutral alkali metal salt of sulphurous' acid in the presence of water.

6. The process for the production ofamino alkyl sulphonic acids which comprisesheating a mineral acid ester of an amine containing at least one hydrokyl group attached to alow molecular alkyl radicle, with a neutral alkali metal salt of sulphurous acid in the presence of water to a temperature between 100 C. and the decomposition temperature of the said initial materials.

7. The process for the production of aminoalkyl sulphonic acids'which comprises heating, a sulphuric ester of an amine containing at least on hydroxyl group attached to a low. molecular alkyl radicle, with a neutral alkali metal'salt of sulphurous acid in the presenceof ater-to a temperature between 100 C.- and t e decomposition temperature of the said initial materials. 8. The process forjthe production oflaminoalkyl sulphonic acids which comprises heating a suiphurieester of an amine containing at least one hydroxyl group attached to a low molecular alkali metal sulphite in the presence of water to a temperature between 100 .C. and the decomposition temperature of the said initial materials.

9. The process aikyl sulphonic acids which comprises heating a sulphuric ester of an amine containing atleast one hydroxyl group attached. to a low alkyl radicle, with sodium sulphite in the presence of water in a closed vessel to 'from about 120 to :about 180 C. 1 I 10. The process for the production of aminoalkyl sulphonic acids which comprises heating a sulphuric ester of a hydroxyethyl amine with sodium sulphite closed vessel to from 11. The alkyl sulphonic acids which comprises heating a sulphuric ester of a tertiary hydroxyalkyl amine corresponding to the general formula -m-osom v 3x I in which R and R1 are R: is an all'wlene group,

about 120 hydrocarbon radicles'and with sodium sulphite in for the production of amino-- in the presence of water in a to about 160 C. process for the production of'aminoalkyl,

about 120 to about ism-c.

12. The process for the of a tertiary hydrokyalkyl amine the general formulaa sulphuric ester corresponding to n-m-ososn RY inwhich R and R1 are R: is an ethylene the presence of water in a closed vessel to from about 120 to about 160 C.

13. The process for the production of aminoalkyl sulphonic acids which comprises heating -,a sulphuric ester of a tertiary N-hydroxyethyl- N-arylamine corresponding to the general formula in which 31s a hydrocarbon radi leand-B1 is an aryl radicle, th sodium sulphite in the presence of water in a closedwe'ssel to from about 120. to about 160 'C. i 4 14. Amino-alkyl sulphonic acids corresponding to the general formula V 1 in which R denotes hydrogen, an alkyl, cycloalkyl, aryl or aralkyl radicle; R1 aralkyl radicle, I contained inn. and-R1 being at -least 'l and-in which R: denotes an alkylene radicle containing at least 2 carbon atoms.'=

Amino-alkyl sulphonic acids correspondin to the general formula r i N-oiH.--som R: v i v in which R denoteshydrogenr-an alkiihxcycloand R1 denotes an the sum of the carbon 'ryl or aralkyl radicle aryl or aralkyl radicle, I atoms containedin R and R1 being at least, I,

nnmmcn ULRICH; 1 PAUL xonanmo.

-o warm.

r the presence of water in a closedues'selto from" production of amino- I alkyl sulphonic acids which comprises heating hydrocarbon radicles and I group, with sodium 'sulphite in denotes an aryl or I the sum of the carbon atoms 

